Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual construtor possui uma grade de 12?
 ###Tabelas: CREATE TABLE first_league (first_league_id AUTO_INCREMENT PRIMARY KEY, Team VARCHAR, Match INT, Points INT, Draw INT, Lost INT) CREATE TABLE current_iwa_champions (current_iwa_champions_id AUTO_INCREMENT PRIMARY KEY, Championship VARCHAR, Champion(s) VARCHAR, Previous champion(s) VARCHAR, Date Won VARCHAR, Location VARCHAR) CREATE TABLE classification (classification_id AUTO_INCREMENT PRIMARY KEY, Driver VARCHAR, Constructor VARCHAR, Laps INT, Time/Retired VARCHAR, Grid INT) CREATE TABLE composition_of_the_15th_seanad (composition_of_the_15th_seanad_id AUTO_INCREMENT PRIMARY KEY, Administrative Panel INT, Agricultural Panel INT, Cultural and Educational Panel INT, Industrial and Commercial Panel INT, Labour Panel INT, National University of Ireland INT, University of Dublin INT, Nominated by the Taoiseach INT, Total INT) CREATE TABLE tour_de_france (tour_de_france_id AUTO_INCREMENT PRIMARY KEY, Height (m.) VARCHAR, No. of times visited INT, No. of HC climbs INT, First time as HC climb INT, Most recent INT)  
SELECT Constructor FROM classification WHERE Grid = 12